Light unit display

ABSTRACT

A light emitting device with a top electrode and a bottom electrode is pushed by a plug to make contacts with either an upper metal plate or a lower metal plate each serving as one of the leads for an electrode of the light emitting devices. The plug is inserted through an opening larger than the light emitting device in the metal plate not in contact with the light emitting device but serving as another lead for the light emitting device. The plug is locked in place by means of threaded screw heads, snug-fit, snap-on buttons or an elastic sleeve. Thus, the light emitting device can be easily replaced without any wire bonding. A plurality of the light unit can be sandwiched between the upper metal plate and the lower metal plate.

BACKGROUND OF THE INVENTION

1. Filed of the Invention

This invention relates to a light display unit, in particular to adisplay unit with a plurality of individual replaceable light emittingdevices.

2. Brief Description of Prior Art

In USPTO publication 2004/0227146, a light emitting device 20 wasdisclosed as shown in FIG. 1. A plurality of two-electrode lightemitting diode (LED) 10 are sandwiched between two metal plates: anupper metal plate 11 and a lower metal plate 12. The upper metal plate11 is coupled to the surface electrode 101 of the light emitting device10, and the lower metal plate 12 is coupled to the bottom electrode 102of the LED 10. The metal plates are clamped together to form a lightdisplay unit. Insulation layer 13 is between the upper metal plate 11and the lower metal plate.

The light display panel 100 comprises a large number of such lightdisplay units 20 as shown in FIG. 2. Each light display unit 20 is wirebonded to a common substrate 15 through wire 14 to form the displaypanel 100. The shortcoming of this structure is that when one of theLEDs is defective or when one of the LEDs needs to change color, it isdifficult to disassemble the display unit 20.

SUMMARY OF THE INVENTION

An object of this present invention is to provide a light emitting unitwhich can be readily replaced. Another object of the present inventionis to provide means for replacing a defective light emitting unit in adisplay panel. Still another object of the present invention is toprovide means to change the color pattern of a LED display panel.

These objects are achieved by not using any wire bonding, but using apressure sleeve to make pressure contact to the top electrode of the LEDand to make electrical contact with the upper metal plate. The sleeve isinserted through the upper metal plate in a hole larger than the LED diesize, after the LED is inserted through the hole. An end of the sleevepresses against the top electrodes of the LED to make electrical contactand to fix the position of the LED. The core of the sleeve allowstransmission of the light emitted by the LED. When the LED is to bereplaced, the sleeve is lifted from the hole and another LED is insertedthrough the hole. The sleeve can be locked in place with screw-thread,snug-fit, snap-on buttons, or slotted elastic tubing.

Alternatively, a plug is inserted through the lower metal plate to pushthe LED against the upper metal plate. Similar means can lock the plugto the lower metal plate.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a prior art LED unit of a display panel.

FIG. 2 shows wire bonding to a number of LED units to a common substrateof a light panel.

FIG. 3 shows the top plate of the present invention with through holesfor the insertion of LEDs.

FIG. 4 shows the first embodiment of the threaded sleeve of the presentinvention to press against the underlying LED for making contact and forfixing the position of the LED.

FIG. 5 shows the top view of the top plate after the insertion of thepressure sleeve.

FIG. 6 shows the AA′ sectional view of FIG. 5 of the LED unit withscrew-thread sleeve.

FIG. 7 shows a second embodiment of the invention with plug-in sleeve.

FIG. 8 shows a third embodiment of the present invention with snap-onbutton at the bottom of the sleeve.

FIG. 9 shows a fourth embodiment of the present invention with elasticsleeve.

FIG. 10 shows a fifth embodiment of the present invention with uppermetal plate windows smaller than the LED unit.

FIG. 11 shows a bottom view from the lower metal plate for the fifthembodiment.

FIG. 12 shows the side view of the fifth embodiment with a bottomscrew-thread plug for pushing up the LED unit.

FIG. 13 shows the side view of the fifth embodiment with the plugpushed-up.

FIG. 14 shows a sixth embodiment of the present invention with asnug-fit bottom plug.

FIG. 15 shows a seventh embodiment of the present invention with asnap-on, push-up plug.

FIG. 16 shows an eighth embodiment of the present invention with anelastic push-up plug.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 3 shows the upper metal plate 21 of the present invention,overlaying a lower metal plate 22. A number of windows 231 are placed inthe upper metal plate 21. Each window is large enough for an individualLED 20 to feed through.

FIG. 4 shows a metal plug 25 in the shape of a sleeve to fit into thewindows 231 in FIG. 3. The plug has a core 251 and thread 252 forscrewing to one of the windows 231.

FIG. 5 shows the top view of the upper metal plate 21 with the metalsleeve 25 inserted. The inner core of the sleeve is smaller than theoverall dimension of the LED 20, so that each sleeve presses against theLED 20.

FIG. 6 shows the cross-sectional view along the section line A-A′ inFIG. 5 inside each window 231. Each window 231 on the upper metal plate21 is threaded with teeth 212 to mate with the teeth 252 of the metalsleeve 25. The LED unit 20 is first inserted through the window 231pressed against the lower metal plate 22, so that the bottom electrodeof the LED 20 makes contact with the common lower metal plate 22. Thenthe metal sleeve 25 is screwed into the window 231 for the top electrodeof the LED 20 to make contact with the upper metal plate 21, which isseparated from the lower metal 22 by insulators 23. The core 251 issmaller than the top area of the LED light unit 20 to produce enoughpressure and to insure electrical contact to the top electrode of theLED light unit 20. Since the metal sleeve 25 can be unscrewed, the LEDlight unit 20 can readily be replaced with ease.

FIG. 7 shows a second embodiment of the present invention. The structureis similar to that in FIG. 6, except that the sleeve 25A is notthreaded. The sleeve is plugged and snug-fit into a window 231 withoutany threads. Other elements refer to the corresponding elements with thesame reference numerals in FIG. 6.

FIG. 8 shows a third embodiment of the present invention. The structureis similar to that in FIG. 7, except that snap-on buttons 255 are placedat the bottom of the sleeve 25B. The snap-on buttons 255 insure that themetal sleeve 25B is well anchored in the window 231. Other elementsrefer to the corresponding elements with the same reference numerals inFIG. 7.

FIG. 9 shows a fourth embodiment of the present invention. The structureis similar to that in FIG. 7 except that the metal sleeve 25C has a cut254, so that the sleeve becomes elastic and can be squeezed into andlocked with the window 231 of the upper metal plate 21. Other elementsrefer to the corresponding elements with the same reference numerals inFIG. 7.

FIG. 10 shows a fifth embodiment of the present invention with thewindows 311 in the upper metal plate 31 smaller than the LED light unit20 and overlaying the lower metal plate 32. The lower metal plate 32 haslarger holes 321 than the windows 311 as shown in FIG. 11. The size ofeach hole 321 is also larger than that of a LED light unit 20 as shownin FIG. 12 so that each LED light unit 20 can be inserted upward throughthe hole 321 in the lower metal plate 32, which is separated from theupper metal plate 31 by insulators 23. In FIG. 12, each hole 321 isthreaded with teeth 322. A plug 35 is screwed upward by means of teeth352 to mate with the teeth 322 in the hole 321 and to push the LED lightunit 20 against the upper metal plate 31 as shown in FIG. 13. Since thewindow 311 in the upper metal plate 31 is smaller than the LED lightunit 20, the LED light unit 20 is anchored below the upper metal plate31 and makes the top electrode of the LED light unit 20 contact with theupper metal plate 31. The LED 20 can be readily replaced by unscrewingthe plug 35.

FIG. 14 shows a sixth embodiment of the present invention. The structureis similar to that in FIG. 13, except that the plug 35A is not threadedbut snug-fit in the holes in the lower metal plate 32. Other elementscorrespond to the elements with the same reference numerals in FIG. 13.

FIG. 15 shows a seventh embodiment of the present invention. Thestructure is similar to that in FIG. 14, except that snap-on buttons 352are attached at the top edge of the plug 35B. The snap-on buttons 352insures that the plug 35B is well anchored in the lower metal plate 32.The elements correspond to the elements with the same reference numeralsin FIG. 14.

FIG. 16 shows an eighth embodiment of the present invention. Thestructure is similar to that in FIG. 14 except that the metal plug 35Cis an elastic sleeve with a longitudinal cut 354 and the a core 353. Themetal sleeve 35C can be squeezed to be inserted into the hole in thelower metal plate 32 to push against the LED light unit 20. After thesleeve 35C is inserted, the squeeze is released and the sleeve 35Cexpands to lock in the hole in the bottom plate 32 and makes contactwith the bottom electrodes of the LED light unit 20. Other elementscorrespond to the elements with the same reference numerals in FIG. 14.

While the light emitting device in the foregoing paragraphs has beendescribed as a light emitting diode 20, it is obvious that a laser diodecan also be used as the light emitting device.

While the preferred embodiment of the invention have been described, itwill be apparent to those skilled in the art that various modificationsmay be made in the embodiments without departing from the spirit of thepresent invention. Such modifications are all within the scope of thisinvention.

1. A light display unit, comprising: a light emitting device having atop electrode and a bottom electrode; an upper metal plate for couplingto said top electrode and a lower metal plate for coupling to saidbottom electrode; insulating spacers for separating said upper metalplate from said lower metal plate; an opening in said upper metal plate;and a conducting plug inserted in said opening to push the lightemitting device against the lower metal plate, wherein said opening islarge enough for said light emitting device to feed through, and whereinsaid plug is a sleeve with inner diameter smaller than the top surfaceof the light emitting device so that the sleeve makes contact with thetop electrode of said light emitting device and the light from the lightemitting device is transmitted through the core of the sleeve.
 2. Thelight display unit as described in claim 1, wherein said sleeve isscrewed into said opening by means of screw threads on the sleeve. 3.The light display unit as described in claim 1, wherein said sleeve issnug-fit into said first opening.
 4. The light display unit as describedin claim 1, wherein said sleeve has snap-on buttons around the bottomedge of the sleeve to anchor said sleeve.
 5. The light display unit asdescribed in claim 1, wherein said sleeve a longitudinal cut to renderthe sleeve elastic, so that the sleeve can be squeezed into said firstopening and lock in said first opening upon releasing.